Apparatus for delimbing trees

ABSTRACT

A tree delimbing apparatus which includes elongated horizontally disposed members that are rotatable and which have cutting members disposed radially outwardly from the axis of rotation, said rotatable members also serving to space the tree trunks away from said cutting members.

United States, Patent Herolf Sept. 12,1972

[541 APPARATUS FOR DELIMBING TREES [72] Inventor: Kjell Oloi GunnarHeroli, Sundsbruk, Sweden [73] Assignee: Kockum Soderhamn AB, Fack,

Sweden [22] Filed: Sept. 14, 1970 21 Appl. No.: 71,929

[ Foreign Application Priority Data Sept. 18, 1969 Sweden ..12891/69[52] US. Cl. ..l44/2 Z [51] Int. Cl. ..A0lg 23/02 [58] Field of Search..144/2 Z, 3 D, 34 R, 309 AC [5 6 References Cited UNITED STATES PATENTSLlewellyn ..144/2 2 5/1968 Bronemo et al 144/2 Z 1/ 1970 Voronitsyn etal 144/2 Z Primary Examiner-Gerald A. Dost Att0meyFred C. Philpitt {57]ABSTRACT A tree delimbing apparatus which includes elongatedhorizontally disposed members that are rotatable and which have cuttingmembers disposed radially outwardly from the axis of rotation, saidrotatable members also serving to space the tree trunks away from saidcutting members.

17 Claims, 6 Drawing Figures APPARATUS FOR DELIMBING TREES Intree-harvesting the delimbing work on felled trees is an essential andtime-consuming part of the upgrading operation, and for this reason manytypes of machines for branch removing purposes have been proposed duringthe years. According to one principle for the removal of the treebranches the felled trees are fed one by one in their direction oflength through the delimbing machine which comprises delimbing memberswhich are movable towards and from the tree trunk, and may consist of,for instance, knives or rotatable cutters each being swingable around anaxis, the knives or cutters forming therebetween a space through whichthe tree can be fed in its direction of length so that during thepassage of a tree through said space the tree is worked by the delimbingmeans. If desired, the delimbing members can be carried by a rotatabledrum through which the tree is fed.

According to another proposition the delimbing operation is carried outbefore the tree is felled. An apparatus according to this principleconsists of a holder surrounding the tree and delimbing members arrangedon said holder, the holder being movable upwards and downwards along thetree, for instance along an elongated frame with driving means fordisplacement of the holder and for the movement of the delimbing means.Also in this type of delimbing machines means are necessary foreffecting relative movement between the delimbing apparatus and the treetrunk in the direction of length of the latter, and the tree can beworked only one at a time.

In still another type of known means for delimbing felled trees thedelimbing operation and the feeding of the tree in the machine iscarried out by a reciprocable, the tree trunk surrounding unit withdelimbing knives, said unit being movable along a frame. During thedelimbing operation the tree is held unmovable relatively to the frame.The delimbing operation can also be carried out by means of an unmovableunit with delimbing knives which unit surrounds the tree trunk. In thiscase the tree is fed through an apparatus by means of feeding rollers.

Finally it has been proposed to carry out the delimbing work by means ofone or more rotatable delimbing members which extend along the entirelength of the tree or the part thereof corresponding to a desired lengthof the logs to be obtained. Such a delimbing apparatus is described inthe U.S. Pat. No. 3 385 331.

The present invention relates to the latter type of delimbing machinesin which the trees need not be fed into the machine in their directionof length but can be fed in the transverse direction, the delimbingoperation being carried out in a very short time. In this machineseveral trees can be treated in the apparatus simultaneously whichpermits economic working in areas with small trees and economic thinningoperation.

The present invention relates to an apparatus of the latter type and theobject of the invention is to eliminate the existing drawbacks in theknown apparatus and to obtain considerably higher working efficiencywhile decreasing the need for manual work. An advantage with theapparatus according to the invention is that it makes it possible to usesimple, easily exchangeable delimbing members. An other advantage isthat the risk for accidents is reduced which is of considerableimportance in view of the high risk for accidents which is usuallyconnected with the upgrading of felled trees. Still another advantage isthat the machine can be fed by means of lifting trucks, cranes or thelike and be controlled per radio by the operator on the lifting truck orthe like. The delimbed trees can be fed out on the same side of theapparatus as that at which the trees are fed into the apparatus whichfacilitates the transportation of logs to and from the apparatus.

An apparatus according to the invention for delimbing trees comprises aframe and at least one elongated, rotatable delimbing tool carried bysaid frame and extending substantially parallel to the tree to betreated and provided with delimbing portions having cutting edges andbeing arranged at a distance from the axis or shaft of the delimbingtool and near the radially outer portion of supporting members securedto the shaft of the delimbing tool and serving as abutrnents againstwhich the tree trunk can abut during the delimbing operation, and theapparatus is characterized in that at least the major portion of thesupport members has a small dimension in the direction of length of theshaft of a delimbing tool and that the support members are spaced apartfrom each other along the shaft of the tool, the delimbing portionsextending essentially axially relatively to the delimbing tool andhaving their cutting edges directed essentially periferally relativelyto the delimbing tool.

The invention will be described in more detail hereinbelow withreference to the accompanying drawings in which 7 FIG. 1 shows thedelimbing apparatus as seen from one side,

FIG. 2 shows the apparatus as seen from above, FIG. 3 shows theapparatus in cross-section, said Fig. also showing the working principlefor the apparatus, and

FIGS. 4, 5 and 6 show details and sections of the delimbing tools.

The delimbing apparatus according to the drawings comprises a mobileframe or chassis 1 by means of which the apparatus can easily betransported between and over working places. A trough or house 2 isprovided for receiving the trees to be delimbed and may be built as, forinstance, a self-supporting construction and in such manner that it canbe closed wholly or partly during the delimbing operation so that nobranches or other objects can be threwn out and cause accidents. Thepurpose of the house 2 is also during the delimbing operation to holdthe trees substantially parallel with each other and with the elongateddelimbing tools 3 and 4. The delimbing tools 3 and 4 are rotated inmutually opposite directions and are carried by bearings in the ends 5of the house. A gear transmission 6 is provided between the drivingmotor 7 and the delimbing tools. If the latter are extra longintermediate bearings 8 may be built in.

FIG. 2 shows the machine as seen from above and also shows two trees 9one of which being too long so that it must be cut off by means of aknife 23 on the end portion of the house 2.

FIG. 3 shows a cross section of the apparatus according to FIGS. 1 and2. The house 2 comprises a lower wall or plate 2a sloping downwardly tothe right according to the figure and an upper wall or plate 2b whichcovers the delimbing tools 3 and 4. It also appears that a grippingmeans 11 of a truck can be used for carrying the trees 9 to be delimbedwhich trees are put on a wall 14 extending along the delimbing tools andswingably connected to the frame 1 by means of the axis 31. The wall 14can be swung up from its lowest position shown in FIG. 3 by brokenlines, whereafter the wall is swung forwardly and backwardly asindicated by the arrow 15. The tree will be rotated during the delimbingoperation by means of the delimbing tools 3 and 4 the lattersuccessively cutting off the branches of the trees so that the trees arefinally fully delimbed; Thereafter the wall 14 is swung downwardly sothat the delimbed tree trunks 12 fall down to the ground on the side ofthe apparatus where the trees were fed to the apparatus, whereupon thetruck with the gripping means 1 1 can remove the delimbed trunks. Thedelimbing tools which rotate with a speed of 400-800 r/min, for instance600 r/min, are provided with delimbing portions in the form exchangeableor removable knives 16 with sharp edges. There are also provided fixedcutting knives or counter-edges 17 at the upper wall 2b and 18 at thelower wall 2a, said fixed knives extending along the entire length ofthe house 2. The wall 14 is driven by the hydraulic motor 24. Thebranches 13 leave the apparatus at the opposite side thereof withrespect to the side where the logs are fed to and from the apparatus.

FIG. 4 shows a portion of the delimbing tools 3 and 4 which comprise ashaft 33 and 34 respectively on which a predetermined number ofsubstantially circular discs 20 are secured spaced from each other asuitable distance. On each disc is one or more cutting steels or knifemeans 16 provided. The cutting steels are provided at such a distancefrom the shaft of the delimbing tool that a free space is formed betweenthe cutting steels and the shaft into which space the branches of thetree can enter to a considerable depth, for instance at least 2 cm,suitably at least 4 cm, preferably at least 7 cm, before they are cutoff by said cutting steels.

The edge 16' of the cutting steels in the shown embodiment is directedin the peripheral direction of the delimbing tool but the edge can alsobe directed obliquely against said peripheral direction. The cuttingsteels 16 are screwed to a plate 21 which is supported by a plate 22extending parallel with the delimbing tools and being fixed to theshafts 33 and 34 respectively. The cutting steels extend freely in anaxial direction, on each side of the respective discs i.e. without beingsupported by the discs and substantially over an equal distance on eachside of the disc. As appears from the drawing the discs of one delimbingtool are staggered relatively to the discs of the other delimbing tool adistance corresponding to half the distance between the discs on eachtool. It also appears from FIG. 4 that the axial length of the cuttingsteels of one delimbing tool is considerably greater than the free spacein the axial direction between the cutting steels of the other delimbingtool, so that the cutting steels of one tool overlap the cutting steelsof the other tool in the axial direction, whereby all portions of thetree-trunk will be delimbed. The cutting edge 16 of the cutting steelscan suitably be provided at equal or less distance from the center lineof the shaft of the delimbing tools as compared with the periphery ofthe discs 20 whereby said steels are prevented from cutting into thewood of the tree trunk. Furthermore, the edge 16 can extend parallelwith said central line, but this is not necessary since it can alsocross the central line under a predetermined, preferably small angle.The periphery of the disc 20 is blunt and the tree trunk abuts againstsaid periphery during the delimbing operation without being damaged.

FIG. 5 shows a cross section B-B in FIG. 4 and it appears how twoadjacent discs 20 on opposite delimbing tools are turned mutually nearlyFIG. 6 shows a cross section A-A in FIG. 4 and it appears that twoadjacent discs on one and the same delimbing tool are likewise turned180 one relative to the other.

In both the latter cases the discs must not necessarily be turned 180but other angles are possible. The essential thing is that the knifemeans of 'one delimbing tool go free with a requiredmargin from theknife means of the other delimbing tool during the operation of theapparatus. It should also be pointed out that more than one knife meansor cutting steel may be provided on one and the same disc 20. The wall14 is swung upwardly and downwardly by means of one or more hydraulicmotors 22 as mentioned above. Thereby the knives will cut off the topend 10 of a tree 9 if the tree is too long. The delimbing apparatus issuitably built with its frame in the form of a self-bearing orself-supporting construction and may, if desired, be built in moduleswhich can be essembled to an apparatus having a length as oredered bythe customer. Suitably the machine is mounted on a chassis which issupported by transportation wheels and with a driving machinery.

In the embodiment described the edges 16 extend substantially parallelwith the axis of rotation of the delimbing tools. However, tests haveshown that in certain cases it can be suitable to provide the edges at acertain angle to the center line of the axis of the delimbing tools andin such case the separate edges of one and the same tool may formtogether a broken screw line around the axis of the delimbing'tool.

In certain cases it has shown to be suitable to provide the discs 20with pins or teeth for more efficient tumbling of the logs during thedelimbing operation. The distance between the discs is generally between5 and 50 cm. The axial length of the cutting edges 16 can be somewhatless equal with or greater than the distance between the discs.

The swinging movement of the wall 14 by means of the hydraulic motors 24is preferably carried out according to a predetermined program. However,the arrangement should be such that the operator of the loading truckhas a possibility to intervene if troubles should occur.

The shown embodiment is not limiting for the invention since the latterdoes not exclude the use of equivalent means and arrangements by whichthe embodiment can be modified within the scope of the invention. Inthis connection it can be mentioned that in certain cases it can besufficient to provide only one rotating delimbing tool in the apparatus.In such case the axial length of the knife means of cutting steels 16suitably can be greater than the distance between the discs 20 andmoreover each disc can be provided with more than one cutting steel.

What I claim is:

1. A tree delimbing apparatus comprising in combination:

a. a supporting frame,

b. at least one rotatable delimbing tool provided on said supportingframe, each delimbing tool comprising:

1. an elongated and horizontally disposed shaft extending substantiallyparallel with the tree trunk to be delimbed,

2. a plurality of radially extending trunk abutting members located atspaced apart intervals along the length of said shaft,

3. the composite peripheral contour of said radially extending trunkabutting members presenting an abutment envelope which limits theproximity of tree trunks to said horizontally disposed shaft, and

4. a plurality of spaced apart cutting members located radiallyoutwardly from said horizontally disposed shaft adjacent the peripheryof said abutment envelope, said cutting members including knives thatextend essentially parallel to the axis of said horizontally disposedshaft.

2. An apparatus according to claim 1 wherein said cutting members aremounted at a substantial distance from each other along the periphery ofdelimbing tool.

3. An apparatus as set forth in claim 1, characterized in that saidradially extending members have the shape of discs mounted around theshaft of the delimbing tool, the major portion of the circumference ofthe discs being circular and concentric with the shaft of the delimbingtool and serving as an abutment for the tree trunks during the delimbingoperation.

4. An apparatus as set forth in claim 1 characterized in that said discsextend essentially perpendicularly to the axial direction of thedelimbing tool.

5. An apparatus as set forth in claim 1 characterized in that thecutting member is a knife member that is exchangeably secured to asupporting plate.

6. An apparatus as set forth in claim 5 characterized in that thesupporting plate is combined with an axially extending plate serving asholder for the support plate.

7. An apparatus as set forth in claim 1 characterized in that itcomprises two delimbing tools disposed in a generally parallelrelationship.

8. An apparatus as set forth in claim 7 characterized in that thecutting members of one delimbing tool are arranged to cooperate with thecutting members of the other delimbing tool during the delimbingoperation.

9. An apparatus as set forth in claim 7 characterized in that theradially extending members of one delimbing tool are staggered betweenthe radially extending members of the other delimbing tool along thelength of the delimbing tools.

10. An apparatus as claimed in claim 7 characterized in that thedelimbing tools are arranged to rotate in upposite directions.

11. An apparatus according to claim 1 wherein the cutting member of oneradially extending member is radially displaced about relative to thecutting member of the next adjacent cutting member.

12. An apparatus as set forth in claim 3 characterized in that the discsof one delimbing tool are turned, suitably about 180, around the axis ofrotation relatively to the discs of the other delimbingtool.

1 An apparatus as set forth in claim 1 \Vl'llCl'l 111- cludescounter-knives cooperating with the cutting member of the delimbingtools, said counter-knives being fixed relatively to the frame of theapparatus.

14. An apparatus as set forth in claim 1 which includes a platform thatis disposed in a generally parallel relationship with delimbing tool andwhich is adapted to be raised and lowered.

15. An apparatus as set forth in claim 14 wherein that said platform ispivotally mounted on the frame of the apparatus by means of a pivotalaxis that extends essentially parallel with the delimbing tool.

16. An apparatus as set forth in claim 1 wherein one end thereof isprovided with means for cutting off the tree trunks to the desiredlength prior to the time that the tree trunks are introduced into thedelimbing section.

17. A tree delimbing apparatus comprising in combination:

a. a supporting frame,

b. at least one rotatable delimbing tool provided on said supportingframe, each delimbing tool comprising:

1. an elongated and horizontally disposed shaft extending substantiallyparallel with the tree trunk to be delirnbed,

2. a plurality of radially extending trunk abutting members located atspaced apart intervals along the length of said shaft,

3. the composite peripheral contour of said radi ally extending trunkabutting members presenting an abutment envelope which limits theproxirnity of tree trunks to said horizontally disposed shaft, and

4. a plurality of spaced apart cutting members located inwardly of saidabutment envelope so that the cutting of trunks by said cutting membersis minimized.

1. A tree delimbing apparatus comprising in combination: a. a supportingframe, b. at least one rotatable delimbing tool provided on saidsupporting frame, each delimbing tool comprising:
 1. an elongated andhorizontally disposed shaft extending substantially parallel with thetree trunk to be delimbed,
 2. a plurality of radially extending trunkabutting members located at spaced apart intervals along the length ofsaid shaft,
 3. the composite peripheral contour of said radiallyextending trunk abutting members presenting an abutment envelope whichlimits the proximity of tree trunks to said horizontally disposed shaft,and
 4. a plurality of spaced apart cutting members located radiallyoutwardly from said horizontally disposed shaft adjacent the peripheryof said abutment envelope, said cutting members including knives thatextend essentially parallel to the axis of said horizontally disposedshaft.
 2. a plurality of radially extending trunk abutting memberslocated at spaced apart intervals along the length of said shaft,
 2. aplurality of radially extending trunk abutting members located at spacedapart intervals along the length of said shaft,
 2. An apparatusaccording to claim 1 wherein said cutting members are mounted at asubstantial distance from each other along the periphery of delimbingtool.
 3. An apparatus as set forth in claim 1, characterized in thatsaid radially extending members have the shape of discs mounted aroundthe shaft of the delimbing tool, the major portion of the circumferenceof the discs being circular and concentric with the shaft of thedelimbing tool and serving as an abutment for the tree trunks during thedelimbing operation.
 3. the composite peripheral contour of saidradially extending trunk abutting members presenting an abutmentenvelope which limits the proximity of tree trunks to said horizontallydisposed shaft, and
 3. the composite peripheral contour of said radiallyextending trunk abutting members presenting an abutment envelope whichlimits the proximity of tree trunks to said horizontally disposed shaft,and
 4. a plurality of spaced apart cutting members located radiallyoutwardly from said horizontally disposed shaft adjacent the peripheryof said abutment envelope, said cutting members including knives thatextend essentially parallel to the axis of said horizontally disposedshaft.
 4. a plurality of spaced apart cutting members located inwardlyof said abutment envelope so that the cutting of trunks by said cuttingmembers is minimized.
 4. An apparatus as set forth in claim 1characterized in that said discs extend essentiallY perpendicularly tothe axial direction of the delimbing tool.
 5. An apparatus as set forthin claim 1 characterized in that the cutting member is a knife memberthat is exchangeably secured to a supporting plate.
 6. An apparatus asset forth in claim 5 characterized in that the supporting plate iscombined with an axially extending plate serving as holder for thesupport plate.
 7. An apparatus as set forth in claim 1 characterized inthat it comprises two delimbing tools disposed in a generally parallelrelationship.
 8. An apparatus as set forth in claim 7 characterized inthat the cutting members of one delimbing tool are arranged to cooperatewith the cutting members of the other delimbing tool during thedelimbing operation.
 9. An apparatus as set forth in claim 7characterized in that the radially extending members of one delimbingtool are staggered between the radially extending members of the otherdelimbing tool along the length of the delimbing tools.
 10. An apparatusas claimed in claim 7 characterized in that the delimbing tools arearranged to rotate in opposite directions.
 11. An apparatus according toclaim 1 wherein the cutting member of one radially extending member isradially displaced about 180* relative to the cutting member of the nextadjacent cutting member.
 12. An apparatus as set forth in claim 3characterized in that the discs of one delimbing tool are turned,suitably about 180*, around the axis of rotation relatively to the discsof the other delimbing tool.
 13. An apparatus as set forth in claim 1which includes counter-knives cooperating with the cutting member of thedelimbing tools, said counter-knives being fixed relatively to the frameof the apparatus.
 14. An apparatus as set forth in claim 1 whichincludes a platform that is disposed in a generally parallelrelationship with delimbing tool and which is adapted to be raised andlowered.
 15. An apparatus as set forth in claim 14 wherein that saidplatform is pivotally mounted on the frame of the apparatus by means ofa pivotal axis that extends essentially parallel with the delimbingtool.
 16. An apparatus as set forth in claim 1 wherein one end thereofis provided with means for cutting off the tree trunks to the desiredlength prior to the time that the tree trunks are introduced into thedelimbing section.
 17. A tree delimbing apparatus comprising incombination: a. a supporting frame, b. at least one rotatable delimbingtool provided on said supporting frame, each delimbing tool comprising: